Commands by mmghaseminya (1)

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display ip address
add this alias in .bashrc to fast check the ip address of your modem router alias myip="curl -s http://myip.dk | grep '' | sed -e 's/]*>//g'"

Mount a Windows share on the local network (Ubuntu) with user rights and use a specific samba user

Retry the previous command until it exits successfully
Executes the previously-run command constantly until it returns 0 (success). Put a

Convert entire audio library in parallel
Uses parallel processing Reiteration of my earlier command https://www.commandlinefu.com/commands/view/15246/convert-entire-music-library Usage lc Old_Directory New_DIrectory Old_Format New_Format lc ~/Music ~/Music_ogg mp3 ogg

Big (four-byte) $RANDOM
Sometimes, in a shell script, you need a random number bigger than the range of $RANDOM. This will print a random number made of four hex values extracted from /dev/urandom.

Display the standard deviation of a column of numbers with awk
This will calculate a running standard deviation in one pass and should never have the possibility for overflow that can happen with other implementations. I suppose there is a potential for underflow in the corner case where the deltas are small or the values themselves are small.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Fast command-line directory browsing
After typing cd directory [enter] ls [enter] so many times, I figured I'd try to make it into a function. I was surprised how smoothly I was able to integrate it into my work on the command line. Just use cdls as you would cd. It will automatically list the directory contents after you cd into the directory. To make the command always available, add it to your .bashrc file. Not quite monumental, but still pretty convenient.

View user activity per directory.
View all files opened by a user in specified directory. The +D option makes lsof search all sub-directories to complete depth, while ignoring symbolic links.

count and number lines of output, useful for counting number of matches
Write each FILE to standard output, with line numbers added. With no FILE, or when FILE is -, read standard input.


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